Personal Findings on Free Flowing Exhaust

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skyshadow07

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That is factual on paper. There are a lot of factors that come with it. For example, if the runners leading up to the H or X are exactly the same length then they would collide. But our engine is transversed across the front so one bank is 2ish feet in front of the other. This means an H or X behind the DPs would be seeing pulses crossing the same point at different times.
 

GotGrip?

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That is factual on paper. There are a lot of factors that come with it. For example, if the runners leading up to the H or X are exactly the same length then they would collide. But our engine is transversed across the front so one bank is 2ish feet in front of the other. This means an H or X behind the DPs would be seeing pulses crossing the same point at different times.
Lol
 

Kevin81

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I'm not super duper clear on the science, but I will say this...its my understanding that inline 4s and V6s should always be single exhaust from a Y pipe, as there is no benefit to even running true duals, especially on turbo/twin turbo cars. "Dual" exhaust on these cars from the factory is for cosmetic purposes. Take the Honda S2000..."dual" exhaust from the factory, but aftermarket exhausts are all single. The Nissan Zs, same. Even the V6 mustang and camaro, there are turbo kits for them, and the ones I've seen have all been single exhaust from y pipes. Helps even out the back pressure, turbulence, etc.
 

skyshadow07

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He used the infamous word.. backpressure. Many friendships have ended because of that word. lol
 

Kevin81

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He used the infamous word.. backpressure. Many friendships have ended because of that word. lol
This is why I say I don't know the actual science of it, lol.

Its always been my understanding that you want even flow from each exhaust port. On an inline motor, that's simple, relatively speaking...just have 1 single manifold with equal length tubing. On a V configuration, less simple, but still fairly simple. Just make sure both sides flow the same amount. But then throw valve timing into the mix. Then turbos? Much less simple.
 

skyshadow07

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^You hit the nail on the head. Too many unknowns for any of us to say whats what. I doubt any of us (off hand) even know the tube length difference of the downpipes. Or how about exhaust pulse speed difference from hitting a turbine. Then there are internal wastegates... oh jeez.. OOORRR, do we know if our engine actually has a symmetrical firing order?

I know I'm going to do a Y pipe. Mostly for weight.
 

Kevin81

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Symmetry sells. If we took everything manufacturers did to heart we wouldn't need to modify our cars.
True that.

To me, they give us a blank canvas. Its vanilla ice cream. Its up to us to make it awesome by adding peanut butter.
 

High on Ethanol

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manufacturers have to compromise to meet requirements and attempt to be the auto-octane tune for every possible elevation, climate, and customer demand. In the end most are left wanting.
 
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